A Botticelli painting has been discovered after experts stripped off dirt and more than a century of yellow varnish.
The work was thought to be an imitation of Sandro Botticelli’s famous Madonna Of The Pomegranate.
But it was discovered to be the real thing when English Heritage conservators cleaned the 15th-century masterpiece.
X-ray testing, infrared studies and pigment analysis revealed that the painting, with its vivid reds, blues and golds, came from Botticelli’s Florence workshop.
Rachel Turnbull, English Heritage’s senior collections conservator, said that after consulting with experts at the Victoria & Albert Museum and the National Gallery, “we are finally able to confirm that Madonna Of The Pomegranate is from the Florentine workshop of master painter Sandro Botticelli”.
She said: “Being able to closely examine and conserve this painting for the first time in over 100 years has really given us the chance to get up-close and personal with the paintwork.
“I noticed instantly that the painting bore a striking resemblance to the workshop of Botticelli himself.
“Stylistically it was too similar to be an imitation, it was of the right period, it was technically correct and it was painted on poplar, a material commonly used at the time.”
She said: “After removing the yellowing varnish, x-ray and infrared examination revealed under-drawing, including changes to the final composition uncommon in straight imitations.”
The 1487 painting, which depicts Madonna and Christ Child flanked by four angels, was bought by diamond magnate Julius Wernher in 1897.
A famous, larger version – the original – attracts crowds in the Uffizi Gallery in Florence.
It was assumed this painting was an imitation, by an unknown artist, because it varied in detail to the original and because of the thick yellow varnish that concealed the quality of the work.
Madonna Of The Pomegranate will go back on display when Georgian villa Ranger’s House reopens to the public.
The property is home to the Wernher Collection – an assortment of more than 700 works of fine and decorative art amassed by Wernher in the late 19th century.
Madonna Of The Pomegranate will be on display at Ranger’s House in Greenwich, London, from April 1.